This invention relates generally to reciprocating floor conveyors and more particularly to an improvement thereto comprising raising and lowering the slats as they move horizontally.
Reciprocating floor conveyors are used in bins, in trailers and on docks for loading and unloading goods. These conveyors typically constitute the floor of the cargo container, or the deck of a loading dock, as the case may be, and comprise a plurality of slats disposed in side-by-side horizontal relation on a support structure. The slats for example in a bin or trailer body may be two inch high by three inch wide tubular or channel metal members of suitable thickness and extend the length of the cargo container. The slats are slidably mounted on a support structure and are reciprocated back and forth in the same plane by a suitable drive system or mechanism to convey materials resting on the slats.
The floor slats are commonly divided into three (or more) slat groups with every third slat being in a common group. To move the goods all slats are moved in unison about nine inches in one direction and then the slats are returned one group at a time to their initial i.e. home position. The goods remain in the advanced position while the respective groups of slats are returned to their home position. Since conveying of the goods is dependent upon frictional contact success can only be attained if the frictional forces on one third of the slats is low enough for the goods to remain in the advanced position on the two thirds of the slats while the slats are returned to their home position one group at a time. In some instances the goods will move back and forth with the slats and thus there is little or no advancement of the goods even though only one third of the slats are returned at a time to their home position. This can be caused by the goods themselves ie physical characteristics such as a bunch of wood pieces of various sizes and/or length and/or due to deflection of some of the slats relative to the other adjacently disposed slats because of the load distribution of the goods thereon.
There are a number of issued patents directed to various features of reciprocating floor conveyors and by way of example and for further information reference may be had to the following:
Foster et al U.S. Pat. No. 5,588,522 issued Dec. 31, 1996
Foster U.S. Pat. No. 5,355,995 Issued Oct. 18, 1994
Hallstrom Jr U.S. Pat. No. 4,966,275 Issued Oct. 30, 1990
Foster U.S. Pat. No. 5,433,312 Issued Jul. 18, 1995
Howe Jr U.S. Pat. No. 4,286,422 Issued Sep. 1, 1981
Foster U.S. Pat. No. 5,911,555 Issued Jun. 15, 1999
Lutz U.S. Pat. No. 5,522,494 Issued Jun. 4, 1996
Quaeck U.S. Pat. No. 5,799,778 Issued Sep. 1, 1998
Foster U.S. Pat. No. 4,907,691 Issued Mar. 13, 1990
A principal object of the present invention is to reduce frictional contact of the goods with the slats that are returning to their home position while they are returning to their home position.
In keeping with the forgoing there is provided in accordance with the present invention means mounting the slats, in a moving floor conveyor, in such a manner that on their return to their home position their upper load engaging surface is below the plane of the remaining slats that are in their advanced and retracted positions and supporting the goods they have carried to that advanced position.